I would do a solid rear door, you will have a lot of leakage from my experience with a tarp rear door. It may work out for you. Where are you mounting the leaf loader?
2002 Ford F250 - XLT - 4x4 - ext. cab
1997 Ford F350 - XL - 4x4 - Diesel - Insert Dump
1997 Ford F250 - XLT - 4x4 - Diesel - some extras
Scag Turf Tigers
Stihl 2-stroke equipment