Diesel return to fuel tank

Hi, I am fitting a 200 TDI into a series 3 lightweight, the fuel tank was originally for petrol, I now need a diesel return pipe to the tank. The tank has been refurbished, so I don't want to weld anything on to it. Has anyone any ideas of how best to do this, I have been advised to return it through the fuel sender?

Later senders have a fuel pick up, so that's possible, but I think they're bayonet fitting, rather than the 6 bolts on earlier tanks. So drill the sender and use a diesel rated bulkhead fitting to get the fuel back in.

Thanks, does the return pipe have to go down to the bottom of the tank? I have heard that if the pipe is short, it can draw air into the system.

It's best, I think, as it doesn't make the fuel froth, but can't see it's all that different from filling the tank at the fuel station.
My 109 TDI returned diesel to the top up the tank for years, I put a tee into the balance pipe between the two chambers in the rear tank.

I think you’re right as I recall the return is shorter than the suction which has a gauze on it, but it won’t draw air in as it’s a return pipe, air can be drawn in via suction pipe if split and tank level low or holed from tank to pump
You can’t return it via the sender as it’s sealed
If yours does not have the blank plate ready you will need to drill holes and screw on as below

Get on ebay etc and find a diesel heater standpipe.

Like this https://www.ebay.co.uk/itm/384647265358?hash=item598ec37c4e:g:O14AAOSwxPJhzsqD

Thanks to everyone the help, much appreciated.