Servo brakes

Dont know if anyone has come across this ... but if they have i would like some advise..

I have a VW based trike running engine, gearbox, swing axles and rear wheels in a one off frame

I did have a 1600dp single solex carb with a vacum advance and also a vacuum servo from the carb intake for the brakes... i assume this was needed when built as the tires are 300 wide and the normal drums where not up to the job... something i can confirm when i managed to crimp the servo hose and lost the vacuum...it was scary

That engine is now toast due to the person who rebuilt it before i got it being a complete idiot... stripped it down to find that they hadnt done the flywheel up, probably as they didnt have the right tool... they tack welded it... needless to say the crank is history... and that was just the first of many issues...some people should not be let near spanners

I now have a 1641 with twin 36 dells... bought from this forum (cheers scott)... Hmmm... what about my servo brakes...no vacuum from the main intake... how do i get round this

My initial thoughts have been

a) drill through the manifold and either tap it or weld a nut to the outside to screw a vacuum connection in.

My question for this would be would i need to do both sides or just one manifold..will it upset the carb balance...or

b) Pay some one to custom make me billet blocks to bolt under the manifolds with connections screwed in (as you can get different hieght manifolds i didnt think this would be an issue).... ive a fair idea on this one ill need to do both sides

Any thoughts welcome