Gerald Miller writes:

On Tue, 24 Mar 2009 22:50:03 -0600, Joe Pfeiffer
wrote:

Depends on whether actual competence is required for metalwork.

I'm replacing the timing belt on my wife's '00 Intrepid, which
requires removing the vibration damper. There's a special service
tool for holding the damper in place while loosening the crankshaft
bolt. Last time I used an old serpentine belt and a clamp instead of
the tool, but this time I got ambitious....

Building a vibration damper holder requires cutting a six inch steel
disk. So, I finished building a circle guide for my sabre today. The
"universal" circle guide at Lowe's turned out to not be universal
enough.

Unwinding the recursion, tomorrow I see if the circle guide will
really help me cut a circle....
When I worked on Senior Son's '68 Firebird 6, I used a flat plate with
three holes to match the Puller bolt pattern with a chain drilled
opening for the retainer bolt. The end of the plate rested against the
frame. this was the only way I could see to hold the crank from
turning other than dropping the pan or using rope in a cylinder.

This tool ends up being pretty similar to what you're describing,
though the balancer doesnt have holes for the puller (as brilliant an
engine design as the Mopar 3.5 is in many ways, the harmonic
balancer is an exception).

I've done this job before on this car, and used a serpentine belt
wrapped around the crankshaft pulley with vice-grips holding the belt
together. I just decided I wanted to duplicate the "right" tool for
the job this time instead of killing another belt (before you tell me
I should replace the accessory belts, they're nearly new. I replaced
the radiator recently, and changed the belts at that time).