Tough converter (TH400)
#4
Some converters are very tight engaging, by wiggling the converter it should help. Mine recently took a bit of effort to get in, but it finally did. Mine was setup pretty tight and when I found the right spot, it slid right in. My recommendation would be to have the trans input shaft face up and try to install the converter that way. I know, it will be dry, but at least if it fits, you know it is properly setup.
#5
just fiddle with it.sometimes i have more luck when i just stop trying and start doing stupid stuff like turning the converter at odd angles or spinning it not really being serious with it,and it will just drop in.go figure.