Underdrive Pulley Help/Questions

[okinawa986]

Considering Pedro's Underdrive Pulley Kit but read that IMS Bearing Replacement should be done before because of the need to shave down the "boss" or Top Dead Center bolt receiver/holder/whatever (not sure of technical term).

Can someone elaborate on why shaving down the "boss" may make this more difficult?

Can enough of the "hole" be left intact to use it as a TDC guide?

Any other problems experienced as a result of an Underdrive Pulley Kit?

Recommend any other kit over Pedro's and why?

Thanks in advance.

[JFP in PA]

When the pin is through the crank pulley and in the TDC boss, it can have a substantial load on it, especially during an IMS retrofit. Because some under drive pulley's require you to cut a lot of material away, the ability of the remaining material to hold the engine at TDC can become tenuous. Some pulley's can actually block the TDC hole entirely, which also makes an IMS retrofit impossible.

With many of these units, to problem isn't the pulley, it is the amount of the pin boss you need to remove.