I had plans to upgrade my ignition on my T-7.4's to the Crane, DUI, or MSD. Teague has never heard of anyone doing it, need some feedback from someone that can verify if it can or can't be done.

Sure you can do it.
On a stock 7.4, it will make absolutely no difference in performance.

Stick with 7.4 ignition. No change in performance, others will chime in

Ditto. If it ain't broke, don't fix it. Put your $$ in the fuel tank.

Agreed, the stock ignition is more then enough.

Well, OK then--thanks guys!!

I changed out my thunderbolt for a pro billet msd 2yrs ago and it smoothed out nice, adjustable advance curve with the differant size springs was nice also. I've read allot of negatives about msd on these boards but I'm happy with mine. New wires and blaster coil at same time.

Replace the stock coil with an MSD Baster 3 High vibration coil, that's what I've done and it works great for 10 years now. Even on a blown 900 HP motor....
P.S. Teague is absolutely no help to the do it yourselfer. They may give you advice if you spend 35,000 or so on an engine though, until it's out of warranty!

My cousin has a pair of Merc 330hp/454cid engines that we did several mods on. The engines made 461hp/510 ft/lbs of torque on Tom Earhart's dyno with the stock Merc Thunderboat distributor/ignition. We added a Crane HI 6M ignition box and PS-92 coil to the Merc Thunderbolt distributor and made a couple pulls on the dyno up to 5500rpm---No Difference in power!

If I anticipate upgrading heads and converting to a carb wouldn't the adjustability of Crane or MSD igntion make it a worthwhile upgrade?