Redundant Brake Boosters Safe? (advanced mechanics)

Im replacing the master cyllinder on my 1978 Chevy C60 2-ton truck with one from that years’ Silverado. It will retrofit fine but only on the condition that I leave the Booster mounted to it. The concern I have is that this truck already has another huge, non-integrated booster located in the undercarriage. The only extra step I have to take to connect the additional one is to add a T-connector so both hose lines can share the vacuum off the carburetor.

My main question is would their be anything unsafe about this setup?

Also, they would probably share pressure in the brake line so one booster would do the majority of the work and the secondary would hardly do anything. Correct?

Could you confirm that it would provide an additional measure of safety, being that if one booster failed the other would come in?

Background: Im doing this primarily to avoid both paying an arm-and-leg for original replacement, and also the fact that the original replacement has the tiniest fluid reservoir for a 2-ton truck versus a substantial one off the Silverado. Also adding it would minimize future replacement costs and possibly add additional safety.