The easy way is taller front and rear tires , One of our JF teams has a John Worm chassis that also had a clearance issue , motor sits low in the chassis, like the pan is 5-6" below the lower frame rail. He now runs 33x10.5x15 MT , but I think the MH 33x12x15 would work better [ 101" roll-out] and he runs Hayden 18" front wheels , 250x18[ 23.75" ]tall rib tires, I also have 275x18 [ 24.25" tall] and 300x18 [25"] tall] . I don't like the look of the 300x18, it's a tire I sell to "T" bucket wheels. Or you can change the angle of the rear end, like one of John Worm's guys did, and change the front axle.
Your combo might like the 33x12 MH, we have a few JF teams running them and some blown BBC and SBC guys . Or you could step-up more and run what the fast A/F guys do run the M/T bubba 16x16 tires , the fast guys are runnning in the 5's, on injected nitro and the fast blown alky are running 6.00's on the bubba's
Let me know if you want more help.
Jon 805-444-4489, cell