One sentence in the OP mentioned a "badly notched gear shift lever". The stock chrome plated gearshift guide's edges are MUCH harder than the mild steel gearshift stick, and road vibration saws clearance from the softer shift stick. I replaced my '72's chromed gearshift guide with an aluminum duplicate, and filled the worn notch in the stick with stainless steel TIG weld, then filed the weld flush and polished it- no replating needed. Cannot tell it's ever been worked on.
BEWARE- undocumented mfg change! I mentioned my successful rework to a friend with an '87 GT5-S, and when a local shop tried to duplicate my work, we found that his late stick was built differently. Seems his stock '87 gearstick was a stack of thin sheet metal pieces edge-brazed and plated, not a one-piece forging like the Ford-era stick. When they tried to fill his worn notch with TIG-welded stainless steel, the whole gearstick fell apart. A used '71 gearstick fit perfectly in his '87, but was extremely expensive. Be advised!