Mounted the engine the other day and torqued the bolts to spec. Went to install the cotter pins and the hole in the bolt isn't exposed enough to install the key. I would estimate there is only 2/3rds of the hole showing. Love tapping the pin with a hammer just deforms the pin. The install uses two standard AN6 washers - one at the bolt head and one on the nut side. I am thinking if I were to change those to the thin version of the AN6 washer that enough of the hole would open up to install the key. Much cheaper than buying four AN6 bolts. Any good reasons that the washers can't be thins?

Thanks

Gary