Which Brake booster - Willwood MC

71 Duster - Previous owner put an 8 3/4 rear with disc front and rear. Rear discs I think are a Leed kit. Front I think might be disc parts he sourced from 73 and up. He mentioned he went with the large bolt patern hubs for a better wheel selection. Also have a Willwood master cylinder w/proportioning valve (1in bore). Since I still have to install the Willwood MC, figure I would put a brake booster on it too. I am unsure which booster to get since the stock MC has a 4 bolt pattern, and the Willwood has 2. Do I get just the Mopar brake booster bracket and a universal booster?

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