power brake conversion question

[pseigmund]

Hi All,

I am trying to upgrade to power brakes on my 1970 Chevy 3/4, 4X4. The brake booster I got was off a 1970 Chevy 1/2 4X4. I thought the booster mounted directly to the firewall but this one mounts to a bracket (see attached picture). After I installed it, I lost about 1/2 of the travel in the brake pedal. Is this normal? Also is the brake booster I have a stock booster for a 1970? I always thought the booster mounted directly to the firewall.
Any pictures of 1970 pickups with power brakes? The motor is a 292.

Thanks for any information.