Brake master cylinder and booster

[jasonda]

I am currently building a 1968 k20 4x4. I am using mid 70s axles and brakes and will be upgrading the manual brakes to power. Before I buy a new master cylinder and brake booster I was wondering is there any difference or advantages to using a mid 70s master cylinder and booster verses the correct year? I know they make different bore master cylinders and was not sure if there are any differences in these years.

[OrrieG]

I used 74 axles on my truck and set it up to use a 74 MC with a 9" hotrod booster so the MC bore and capacity would match the brake caliper and rear wheel cylinders. have only test drive it twice around the block but the brakes will put you thru the windshield. From 85 to 2000 I drove it with a manual MC with no issues too.