You can use a fitting that is -10 on one side to screw into the pump and -8 on the other. My Superflow (now Magnaflow) pump/filter combo uses a -12 in and out of the pump/filter assembly. I use 2 -8 lines into a trick "Y" that goes -12 into the pump and I use a -12 to -10 fitting on the outlet side.
Going -10 to -8 is not a big deal at all....it's one fitting no larger (maybe very slightly larger) than the 3/8 pipe to -8 that's in your Holley pump now. I'm pretty sure that Barry Grant sells the fittings your after, radiused inlet....real nice....if not, I know Magnaflow does.
I'm not a big fan of Barry Grant stuff in general, although I have used his pumps and regulators without problems in the past. In fact, I have a BG regulator on my car right now....I like the Magnaflow stuff. I got a good deal on mine when it was Superflow and I've sent it in for a service/upgrade once in the last 10 years. Had I not gotten such a good deal on it, I would have probably gone with the BG 400....I also like the fact that the pump and filter are one unit, the whole mess is only about 8" long without any fittings on it.
BTW, my car was running out of fuel with a Holley blue pump with a 19# spring in it when the car ran an FE....it picked up a couple tenths and about 3 mph with a good fuel system.
460 powered 1967 Comet Cyclone
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