From my knowledge, I think you could. My 2002 has a TKO500 in it which is what the TKX is based off (3650 platform) and as far as I’m concerned the main issues would be bellhousing mating, input shaft, and clutch. I’m sure you would need a custom driveshaft or a T5 length one, but I’m not positive.

After looking online, I found this:

SBF 302, 351 Tremec TKX 5 Speed Transmission Installation Kit, 450 HP

TKX transmission kit provides essentials to fit to your small block Ford Includes 5-speed Tremec TKX manual transmission rated for 600 lb-ft of torque Fits small block Ford engines including 289, 302, 351, and 347 stroker Available in 28 oz and 50 oz external engine balance options Matched...

www.speedwaymotors.com

Should answer most questions.

 

I have a TKX now in my 1970 (same body as a 1969) and before that I had a TKO in the car. It will bolt in without any modifications to the transmission tunnel. Depending on how your car is set up will tell you what you have to do to install the TKX. Depending on which bellhousing you use, you will probably need a spacer between the bellhousing and the transmission. I have the spacer in mine. Clutch system is another thing you have to look at. I have a hydraulic throwout bearing and I absolutely love it. Driveshaft was something I had made at my local shop since my car didn't come with one when I bought it. When I put the TKO in my car, I did have to notch the transmission tunnel support. The TKX did not need the support notched. You'll also need to check the rear axle pinion angle versus the transmission output shaft angle to ensure they're aligned.

The TKX in my car

 

I put a TKX in my 69 mustang with a 351w. It fit. But it is tight to the underside of the trans tunnel. I bought everything through modern driveline. They provide a shifter that has an offset which prevents the need for cutting.

 

Fantastic! Glad to see that they fit!

 

The only issue i had was this. Barely enough space for a sheet of paper. Had to cut a small 5mm strip away.

Other than that, everything went smoothly.
I went from AOD to TKX and had to have my driveshaft reworked.

 

Has anyone put a TKX in a 69 behind a 428? Does it work with stock exhaust, power brakes etc. Also, I only found one bellhousing for an FE and its cast iron. Would kind of rather have an cast iron bellhousing like the originals for the toploader.