Ink and paper trials on the groups two new Goss Universal 70 presses at Portsmouth and Peterborough are taking place.
They are on the verge of full production.
The firm is also close to completing the Goss group-wide upgrade of its production facilities at Northampton, Peterborough, Scarborough and Falkirk.
The proposed acquisition of RIM, which should be completed by 12 April, would bring RIMs production facilities at Sheffield, Bonnyrigg, Preston, Morecambe, Harrogate, Dewsbury, Burnley and Blackpool under the Johnston umbrella.
Johnston Press chief executive Tim Bowdler said: "RIM has its own presses, but there could be some re-organisation of printing. Obviously well look at the most efficient way to produce all our titles."
The Competition Commission is still considering Johnstons proposed acquisition of eight titles from Trinity Mirror, which was agreed last July. However, these titles would be split between Johnston Press existing production sites.
For the year to 31 December the group reported a 4.6% rise in pre-tax profits to 68.5m on turnover of 300.6m.
Bowdler said the group was buoyant and weathering the general advertising downturn well. It also expects to increase its revenues.
Story by John Davies
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