I just did this exact same swap in my 67 200ci coupe with 3-speed manual. Here's what I did and it took about 3 hours to complete.I used a T5 World class out of a 1985 thunderbird turbo coupe car and I bought a steeda tri-ax shifter which I love.Shop around and you can get those shifters for cheap. I ordered the kit from mustangs unlimited part number TRA670534 01 ,it includes the adapter,trans crossmember,slip yoke,trans mount and all associated hardware.You will need to order a new pilot bearing when using that 4cyl trans it is SKF 6202-2RSJ that is part number,just google it or order from auto zone online is what I did.You can buy a stock clutch setup or use your old one it's up to you. I had my driveshaft shortened an inch and then put a new end on it to match the t5 yokes u joint size, cost 130 bucks to do the driveshaft. That is pretty much it. Might have to buy a diffrent speedo gear,but the original cable and everything will work with t5. Any questions just ask or pm me. hope this helps
Edit: i forgot the most important part, this is a great swap and made my car so much more fun to drive and it is about twice as fast as before, drove it 80 miles yesterday and the fuel gauge barely moved. Cruised 75 down the interstate at about half throttle,had to keep it floored before to maintain speed. The 4 cyl trans has the right gearing for these 6cyl motors and I would recommend this swap to anyone.