If I redo it myself, I will probably try to emulate the OE way of using a high strength adhesive and bushing material. I know some mounts are heat pressed, but still have some sort of a bonding agent. A bolt through the bushings would really do opposite what it was designed to do. Also the center has those 2 loops that keep everything together while allowing the mounting plates to move I think to absorb driveline shock.

Richard E
1989 Montero - Stock-ish
1989 V6 Auto Raider - 5.3 Vortech Swap.
1987 Mitsubishi Starion 2.6t, soon to be 3.5
1983 Honda XL600R