Oooh I stand corrected. I was thinking the 20-131 setups.Are we talking about the Holley 20-185 mid-mount kit? I''ve got a couple of the old R4 compressors , a few alternators and an S10 power steering pump or two. It's all been sitting for years. I'm not sure these will fit using the 20-131 brackets, looks like Holley has specified certain gm units. The 20-185 is costly but comes with everything and its all new stuff. I'm thinking longevity and ease of installment.
The 20-185 looks good, what are you running for rad/fans? If it were me I'd cut the core support and move the rad farther forward to gain more in front room. Even w/ a condenser there's still room to be gained recessing forward. Only exception is if you run an aux-trans cooler infront of the condenser then you're out of room .
I will say the one thing I like about that kit is that it uses the longer arm truck style tensioner, not the short arm vette style tensioner. The longer arm generally has better belt control due to the advantage of lever where the short style relies more on spring tension which isn't that linear sadly. The way the routing runs on the 20-185, the belt is going to be nice and short so from a belt perspective definitely like the 20-185.
Only downside I see is that there is less belt-wrap on the crank pulley, but without big horses that won't be an issue I don't think, plus there's always the HD tensioner swap but that can shorten accessory bearing life.