Keep plugging away at it. Believe me, I know what it's like to make slow progress. I've been working on my car for about 3 years now.
On a side note, are you really parting out the '99? I could probably use some parts.
1998 MB E300 - 194,000 miles. Current/future mods: 7.5mm pump elements, Holset HX40 Turbo feeding Eaton M90 supercharger through custom fabbed intake system. Aeroturbine muffler, scratch-built 4" stainless exhaust. EGR eliminated, ECM recalibrated, modified rack position feedback circuit. Porterfield RS brake pads, Bilstein sport shocks, VDO EGT, oil and boost gauges.
2000 Ford F250 - 150,000 miles. Current/future mods: DP Tuner 3 map chip, scratch-built high flow intake, high output IDM, open circuit fuel system, ball bearing turbo, South Bend full metal clutch, slotted and drilled rotors. Autometer Sport Comp EGT and boost gauges.