You may not need a new gasket, they are designed to be reused, yet if any obvious damage, replace. Be sure to clean everything well when reassembling. Diesel Hi test, I think, is to just dump in tank. Might be just fine, don't know. If you do a purge, THEN replace filters, as you may have some, high tech term comming up, gunk, roaming around that you want to capture in current filters and not contaminate new ones. You might want to order a filter or two extra, you're gonna do this more than once, right? to beef up order. Perhaps a PS filter, gaskets, such as oil cap, misc "o" rings. Oil filter housing cap has a couple of rings 0159979448, oil dipstick seal, one 0069972645, master cylinder gasket, two 0002950050, I think, front crank seal, one 0119972247, and metal seal ring, one 6150310051. Make sure all these will fit a 240. Cigar hose, pricey, on the 82 I use just a fuel line. Various vac lines. Other items, maybe, check their site. Glove case 1000. Not fimiliar with Sanitex.

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