I would put a RV or towing kit in it. It will bring up the line pressure so it will have better clamping force for heavy loads. It's not extreme like a Shift kit. A shift kit will be super hard and quik shift. THis is a happy medium between that and a soft stock shift.
If you pull the tranny yourself most small non chain tranny shops will rebuild it for between $300-400. Parts total to rebuild one including new Steels, Clutches and seals with a flush kit and rebuilt converter is in the $125 range. Not really hard to rebuild one. Pretty straight forward. One thing that sometimes happens is the splines on the stator shaft (the shaft the converter rides on) will start stripping off. It's part of the pump assembly and you will have to get a rebuilt pump to fix the problem. I got a rebuilt pump, used sprag and forward drive drum from local tranny place for $75.
Previous owner liked doing neutraldrops and blew the sprag and trashed the drum.
I bought my parts from a Place called Delta automotive. They sell to tranny shops but will set up an account for and individual. You can also get stuff like chains for your 203 from them. Don't forget to flush the cooler. If you don't have a AUX cooler get one. 9 out of 10 tranny failures are heat related.
