Can't now see the Old Firm joining the Premiership, maybe a few years back when all the top names were up in Scotland they may of had a chance of mid table in the Premiership, but not anymore. They would struggle for the first few years until they got the money in and could pay for the top names again, then they could be competitive. But with the present teams they would struggle for yop 6 in the Championship IMHO.
Plus they would have to turn their back on European Football, having been guaranteed Champions League and UEFA Cup Football in Scotland.
But if we remained in the EPL then we would get approx three times (£30m)more money than we would out of a normal year in the Champions League (£10m).
Do not see it happening myself. Every English club below the PL would want the spot if they were being handed out. If, and say if, we (Rangers) were ever to be invited to join the English leagues then we should work our way up.
Having said that, if Sky said get Rangers and Celtic in the league or kiss goodbye to our money then that may be a more likely way of it happening.