Topic: New builder here

[Lord Helmet]

I'm in Atlanta - been riding most of my adult life and decided I'd like to get deeper into bikes by building.  I just finished a 1970 CL450 frame off restomod and now that I've learned how things go together and work and made a ton of mistakes I'm going to do a full cafe build on a 1972 CB500 I just picked up. 
I just stripped it and am in the middle of a top end rebuild (compression was bad) and I'm looking ahead to the front end.  I want to upgrade the brake for safety as well as looks (I track a Street Triple R so I insist on good brakes on my machines).  Like most everyone I'm on a budget (my CL450 build went WAAAAY over budget) so I need to be smart about this. 
I want dual disks for looks but I want the bike to keep the vintage look so no upside down giant fork setups here.  Just something classy and that looks like it belongs.  I also don't want to spend on Cognito Moto conversions etc I need the money put elsewhere in the bike.  I would like to keep the stock geometry or as close as possible.  I would like to go to an 18" front.  I prefer spokes but I'm ok with another style if the opportunity pops up and it makes fiscal sense.  I've done a lot of searching but there's so much conflicting info I thought I'd see if someone here can chime in and help.  I'm building it at a community bike shop so I have access to some tools. 
From what I've found it seems the GL1000 front end is the cheapest idea - but there seems to be an issue with the length of the forks/steering stem.  Not sure how much work/cost it is to work that out.  A friend also has a set of the older conventional R6 forks (or maybe it's CBR I have to double check).  I have a lead on a guy with a '78 GL1000 complete front end (and MC).
Any help GREATLY appreciated.  If I've missed the right thread please point me in the right direction.  I know this has been covered a lot but again there's so much incomplete or questionable info I'm hoping to find someone who's done exactly what I'm trying to do.
I also read somewhere that the CB500s have the right fork caliper mounting points they just need to be drilled/tapped but my bike doesn't have that, just the fender mounts sadly...
Here's a pic of my CL450 restomod.  Frame off build, everything is refurbished or new.  Lots of money and time and blood and sweat went into this so I'm sad to have to sell it but I need the money to do my new build.

Thanks-

[calj737]

500 lowers don’t have mount for another caliper. Probably the GL stem is about .750 longer than the stock 500, so you can press it out and use the stock 500 stem in the GL lower.

The R6 is a popular and successful upgrade, you simply need front axle spacers to make it work out.

[754]

We just put a GL Fork on a 750 last night and did not use a spacer.

 Best bang for the buck if you can handle a Comstar 19  is 77/78 Honda 750 f fork, dual thin light discs..
 Worth looking at.

[calj737]

We just put a GO Fork on a 750 last night and did not use a spacer.
 Best bang for the buck if you can handle a Comstar 19  is 77/78 Honda 750 f forkm dual thin light discs..
 Worth looking at

A 750 doesn’t need spacers, but a 500/550 does. 

[MD]

Welcome from NE MN,

Looks like you are having fun with the project.

-MD

[Gurp]

For your 500 you can swap cb750 tubes and lowers in. On my cb550 i have a set or 8+ tubes with 74 750 lowers. Used the bikes stock axle (cb500) as well.

[OldZaskar]

Hey Lord Helmet... Would the lowers from a '77 CB550 work for your build? They appear to have the mounts on the right side/lower. I haven't a clue what fits what on these bikes. But, I do have a '77 CB550 parts bike... and I'm in Atlanta.

[Lord Helmet]

Wow crazy I was just about to ask the forum that question.  I researched that the 550s had casting on the right fork for a caliper but don't think they are drilled/tapped.  Anyone know any reason I can't just swap my 500 right lower for the 550 and drill/tap the holes for the 2nd caliper?  That sounds like what I want....would look completely at home on the bike and would give me the dual disks I need.  I'll do some more research to make sure but if anyone has done this or knows the answer please let me know...

Thanks~

[Gurp]

This is a great forum man. Full of very knowledgeable and generous peepz that loved old hondas