[special-K]

Looks like you could spin the flanges to the area between bolts to gain another 1/4"... almost double the distance. Running down the road there as air cooling going on, so no worries there. I run full length headers, so never had the situation you have. Lots of people running 3/4 length Sandersons and I've never heard of any issue with heating crankcase oil temps. If I was adding any lines that carry crankcase oil with possible leak potential It would be for an oil cooler before a remote filter. I'd think that would over compensate for any heating from the headers and still offer cooler oil temps overall.

As far as wrapping holding heat in goes, the filter isn't intended to dissipate temps and the oil passing through will be the same temp throughout the engine. A wrapped filter (if you even had the room) would hold in no more heat than the block itself. On starters, with normal start-up they don't make any heat worth considering, while the exhaust is a constant source of high temps that the wrap insulates against. Not a bad thing.