You might want to clean the rust and crud out of the rotor. The picture is a little blurry so I can't see any evidence of arcing but it's not a good idea to have a bunch of crud that close to the HT connection to the cap.
Don't re-install the ignition module without heatsink grease. It'll burn up pretty quick. You can use PC CPU heatsink grease. Super Lube 98003 works. DO NOT USE DIELECTRIC GREASE!!!! Dielectric grease is an insulator.
Stay away from the Chinese crap parts. You can get OEM GM quality parts you just need to know what you're looking for... AC Delco Professional and Delphi are GM OEM parts and they aren't that expensive. The yard machines may have the Chinese garbage. $5 for used garbage is worse than the new Chinese garbage.
A brand new AC Delco D1943A ignition module is right around $35 brand new on Amazon. The Delco modules keep working for a long long time. How much do you get paid per hour?... that $5 ignition module that may last for a few weeks or months probably actually costs you nearly what the new Delco or Delphi part does when you factor in your precious Saturday time to drive to the yard and pull the unknown condition part.
If you figure the pickup coil is borked you can get a brandy new GM Delphi CE10005 small cap HEI pickup coil around $10 from Rockauto.
The new GM Delphi GN10048 ignition coil is right around $20 from Rockauto.
Get the Mercury/Mercruiser 808483Q1 Marine V8 cap and rotor kits with brass terminals... They are right around $30 for a kit. Brass terminals will run around 50,000 miles aluminum will run a third to half of that.
The stock 1990 RV series has a 12059473 two position Weatherpak tower on the sender and fuel pump power wires and a ring terminal on the sender ground. The mating shroud half is on the chassis wiring.
There's a two terminal connector inside the tank on the fuel pump and the sender wire runs right to the rheostat windings.
Got a picture of the connector you're trying to match?
This guy is stripping down and re-building a small cap TBI HEI on a T400 CK model... It's the exact same unit as your RV series. Not much to em compared to the large cap HEI.
Be sure to set the shim pack between the gear and the housing so the end play is in the 0.015" - 0.020" range. Try to get it as close to 0.015" as you can... Yes the ECM will compensate but it's better to give it less to worry about.