You need a C5 BW1350 shifter, and a 1986-1987 shift arm from a BW1350 manual that was behind a FM145 manual transmission. It’s the same length as the shift arm on the 1983-1985 C5/TK4/TK5/FM145 fixed shift arm 1350 but is removable. The BW1354 shift arm is the same length as a FM146/A4LD BW1350 shift arm.
1983-1985 fixed arm BW1350:
A4LD/FM146 BW1350 shift arm vs shorter trans shift arm.
Long BW1350 vs BW1354 arm.
BW1354 arm
C5/TK4 BW1350 shifter
1986-1987 FM145 BW1354 arm
Short arm on BW1354 with C5 BW1350 shifter low range.
Short arm on BW1354 with C5 BW1350 shifter 2Hi.