The 39x18.5 Mickeys I had were on my old '82 Bronco, which I sold last year. it had 9" of lift, and Bushwacker cutout fender flares, which was just about enough not to rub. I'm not sure how wide or tall you can go with only 4" of lift. I know someone with 3" of lift that is rubbing with 35x12.5 tires, and I don't know if one more inch buys you all that much more clearance. Try reposting your question in Upgrades and Aftermarket, you'll get a lot more replies there.
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Philip Casciola
'00 F350 4x4 Lariat Crew Cab LWB DRW V10 3.73 (Red Clearcoat/Parchment Leather Interior)
Flutter-Less '01 Y-Pipe, Leer 100XL Browning Edition Cap (On order)
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Y-Pipe Pictures