It's kind of like the Blazer issue; by the time you bore out the ID for the insert, the wall is starting to get pretty thin.
I'd have to go and measure an SL/Special barrel to be sure, but on the Blazer, the side walls were going to end up just 0.050" thick or so. Or was it less? I seem to recall thinking the barrel would end up just a touch thinner than the insert but I might be misremembering.
The SL barrels are a bit larger in OD than the Blazers, so it's not as much of an issue, but they'd still be kind of thin.
And besides all that, you'd have to have a new pump made for the SL, and it'd never fit over a Freak body- at least, not one that has the Freak tip threading.
