[Jack21]

Couple of things to consider;

Shopping for US made parts in the UK is not a big deal. I buy OEM spec AC & Cobra parts from UK and they get here in about the same amount of time as here in US. The banks do all the financial fiddling to convert pounds to dollars. 1 pound is roughly equal to 1.6 dollars.

If you can afford it, get a hydraulic roller retrofit cam for your Cleveland. It's like adding 30 - 40 more cubic inches. Look at Crane and Comp cams hydraulic roller retrofit offerings.

Make as truthful of an assessment as to your driving style as you intend to drive the car. Here's why. Most street driving is done between off idle to 3500 RPM. 95 - 99% of your engines life will be spent in this range. It's OK to be a little conservative in duration. 220 - 230 degrees on the intake side will give you a nice powerband from 3000 - 6000 RPM but you may only rarely use it. A 210 - 220 may look disappointing on peak HP numbers on paper, but may suit your needs better in the RPM range you'll do most of your driving in.