I’ve never used any tools to put a tyre on the rim even a Marathon Plus on a Brompton. The technique is to roll and push to make sure the tyre is in well of the rim. In the end it just pops on. As a last resort I may use a bit of soap to help it seat.
Do you carry soap when you are out on a ride.🤷🏼♂️

so will source something better soon to replace it.
,BH is really pleased so hopefully give it a proper ride tomorrow.