#1: You should be fine, lots of folks do "partial underdrive" you just wont free up quite as much hp (nominal difference)
#2: Honestly, I dont know much about what crawlers need to be able to do. If I was in doubt, I would err on the side of caution. Too much cooling?Good. Not enough? Bad.
J
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'66 Mustang Coupe- AKA "Lenore" *on disability for a (long) bit*
'93 GT Mostly stock AKA "Fawkes"
Rice Haters Club Member #239
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